RELEASE: 1.6.0 (#1682)

* Update CHANGELOG

* RELEASE: 1.6.0

Author: jfreire-unity

Packages/com.unity.inputsystem/CHANGELOG.md

@@ -8,9 +8,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 Due to package verification, the latest version below is the unpublished version and the date is meaningless.
 however, it has to be formatted properly to pass verification tests.
 
-## [Unreleased]
+## [1.6.0] - 2023-05-25
 
 ### Added
+- Added internal `InputSystemProvider` class for the new `InputForUI` internal module. `InputForUI` allows the UIToolkit to have a single dependency for input events, regardless of using the new input system or the legacy input system.
 - Added `InputSystem.customBindingPathValidators` interface to allow showing warnings in the `InputAsset` Editor for specific InputBindings and draw custom UI in the properties panel.
 - Added `InputSystem.runInBackground` to be used internally by specific platforms packages. Allows telling the input system that a specific platform runs in background. It allows fixing of [case UUM-6744](https://issuetracker.unity3d.com/product/unity/issues/guid/UUM-6744).
 - Added new UIToolkit version of the `InputActionsAsset` editor. Currently this is incomplete (view-only) and the existing editor is still used by default.